Avoid more temporary ranges in connection with various TextIterators.

Source/core/html/HTMLTextFormControlElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 375 matching lines @@
         newSelection.setWithoutValidation(startPosition, endPosition);
     newSelection.setIsDirectional(direction != SelectionHasNoDirection);
 
     frame->selection().setSelection(newSelection, FrameSelection::CloseTyping | FrameSelection::ClearTypingStyle | FrameSelection::DoNotSetFocus);
 }
 
 VisiblePosition HTMLTextFormControlElement::visiblePositionForIndex(int index) const
 {
     if (index <= 0)
         return VisiblePosition(firstPositionInNode(innerEditorElement()), DOWNSTREAM);
-    RefPtrWillBeRawPtr<Range> range = Range::create(document());
-    range->selectNodeContents(innerEditorElement(), ASSERT_NO_EXCEPTION);
-    CharacterIterator it(range.get());
+    Position start, end;
+    bool selected = Range::selectNodeContents(innerEditorElement(), start, end);

[yosin_UTC9, 2014/09/12 01:02:24]

It seems utilizing |selected| makes cleaner.

if (!Range::selectNodeContens(...)) 
  return VisiblePosition();

[Mads Ager (chromium), 2014/09/12 10:52:08]

Done.

+    ASSERT_UNUSED(selected, selected);
+    CharacterIterator it(start, end);
     it.advance(index - 1);
-    return VisiblePosition(it.range()->endPosition(), UPSTREAM);
+    return VisiblePosition(it.endPosition(), UPSTREAM);
 }
 
 int HTMLTextFormControlElement::indexForVisiblePosition(const VisiblePosition& pos) const
 {
     Position indexPosition = pos.deepEquivalent().parentAnchoredEquivalent();
     if (enclosingTextFormControl(indexPosition) != this)
         return 0;
     ASSERT(indexPosition.document());
     RefPtrWillBeRawPtr<Range> range = Range::create(*indexPosition.document());
     range->setStart(innerEditorElement(), 0, ASSERT_NO_EXCEPTION);
@@ skipping 547 matching lines @@
             Text* textNode = toText(node);
             size_t firstLineBreak = textNode->data().find('\n', isPivotNode ? pivotPosition.offsetInContainerNode() : 0);
             if (firstLineBreak != kNotFound)
                 return Position(textNode, firstLineBreak + 1);
         }
     }
     return endOfInnerText(textFormControl);
 }
 
 } // namespace Webcore